Field of the Invention
This invention relates generally to eyeglass lenses, more particularly to eyeglass lens edges shaped for greatly reduced light reflection.
Description of the Prior Art
Eyeglass wearers typically experience edge reflection light effect when wearing corrective lenses, especially in intense light environments and/or when wearing “rimless” or partially rimless glasses. This edge reflected light is due to the flat shape of the bottom edge of the lens, such as may be formed by a traditional wheel edging method. In this traditional wheel edging process, the obtained lens edge has a generally flat shape, especially in rimless lens designs. This flat shape will cause significant light reflection into the eye of the wearer. FIG. 1 illustrates fragmented prior art flat-edged lens 100 having flat bottom edge 101, and light 102 reflecting from flat bottom edge 101 into wearer's eye 103. Reflected light 111 will typically be even more intense if the lens edge is polished, such as in rimless lens shapes and when the wearer is under strong indoor light or under a night lamp. As a result, an eyeglass wearer will typically feel discomfort, and/or will typically be distracted, when wearing this type of flat-edged lens. The edge light reflection directs uncomfortable light into the wearer's eye and even limits the near vision area due to the edge reflection interference with the field of view. Such edge light reflection typically manifests as a dark edge along the bottom of the eyeglass lens, which may partially obscure the wearer's field of vision and/or distract the wearer.
Two known lens treatments related to lens edge improvement for eyeglasses include application of an anti-reflective coating on the edge of the lens so that edge can be somewhat less visible and applying color on an edge of the lens for aesthetic reasons. However, these treatments are not linked to edge light reflection improvement.
Edge treatments for other types of lenses, such as contact lenses, intraocular lenses and camera lenses typically deal with reducing the scatter, or diffraction, of light across the lens. Such edge treatments for contact, intraocular and/or camera lenses may include edge beveling, grooving, roughing, and/or other texturing. However, such treatments to address light scattering, or diffraction, of light across the lens do not reduce the visibility of the edges of these lenses for a user.
One common method of ophthalmic lens edge treatment involves putting a bevel shape on the edge of a lens. This bevel can be put on both surfaces of the lens. However, this kind of treatment is not useful for reducing edge light reflection and edge visibility.